HttpListener{
  this.port=port;
}
start{
  NioServerSocketChannelFactory channelFactory=new NioServerSocketChannelFactory(Executors.newCachedThreadPool(),Executors.newCachedThreadPool());
  ServerBootstrap bootstrap=new ServerBootstrap(channelFactory);
  bootstrap.setPipelineFactory(new HttpListenerPipelineFactory(receiver,path));
  Channel channel=bootstrap.bind(new InetSocketAddress(port));
  allChannels.add(channel);
}
stop{
  ChannelGroupFuture future=allChannels.close();
  future.awaitUninterruptibly();
  channelFactory.releaseExternalResources();
}
